Compression ratio is also what makes engines like Mazda's Skyactiv-G engine so efficient. The first of a wave of new high-compression and variable-compression engines from Mazda, ...

The static compression ratio (sometimes called the mechanical compression ratio) is a handy reference that engine builders use to build and describe engines, but no two engines with the same CR ...

Racing engines tend to be very high compression, with NASCAR engines, for example, having a compression ratio of 12:1. High compression is also more efficient, so it would seem reasonable to ask ...

These engines require such a high compression ratio because diesel fuel is less volatile than gasoline, so it's harder to ignite under the same conditions. This is where the piston shape kicks in.

The Skyactiv-X engine has been designed to have a very high compression ratio—16:1 in fact—and to use a very lean air:fuel ratio, but both of these are just below the threshold needed for HCCI ...

Increasing an engine’s compression ratio is a proven way of unlocking extra horsepower, but there’s a point of diminishing returns. The team at Garage 54, the Russian mechanics who built a V16 ...